The present invention relates to a technique for recording information on an optical disc.
JP-A-2003-85753 (Patent literature 1) says: “A recording waveform according to a write strategy in the present embodiment includes a top pulse 40, an intermediate bias part 41 and a last pulse 42. The part of the recording pulse waveform excluding those pulse parts is maintained at a level of read power PR. The write strategy employed in the present invention uses binary write power. The top and last pulses 40 and 42 have first write power Ph, and the intermediate bias part 41 has second write power Pm, which is set so as to be higher than the read power PR and lower than the first write power Ph.”
The Patent literature 1 also says: “When a space between adjacent marks is short, it is effective to shift the end positions of the adjacent record marks, thereby forming a shorter mark than the actual one.”
JP-A-2000-30254 (Patent literature 2) says: “In a method of recording a shortest mark and other marks on an optical information recording medium, using respective different record strategies, the point is to select a write strategy such that a recording power in which a jitter containing all the record marks or a jitter containing only the shortest record mark is minimum is substantially equal to the recording power in which a deviation from a theoretical value of the longest record mark is minimum.”